Whether for historical inquiry, or simply to appease curiosity, people often wonder what day of the week certain events took place, or will take place. For example, some may wonder what day of the week it was when Pearl Harbor was attacked. Some may wonder what day of the week the Declaration of Independence was signed. Some may wonder what day of the week New Year's Eve 2999 will be. And still others may wonder whether there has been a Friday the 13th every year.
While it may be possible to determine this information by performing conventional calculations, such an approach is not desirable because 1) such calculations are long and complex and, as such, are not within the abilities of most people; and 2) their complexity and the level of expertise required to perform such calculations makes them exceedingly prone to error.
Therefore, there exists at present a need for a simple and portable means for calculating calendar information. Each of the foregoing issues, as well as others, is addressed by the present invention.
The present system is a truly perpetual calendar system, since it includes all possible months from January 0001 in the Julian calendar system into the foreseeable future in the Gregorian calendar system. This information can be displayed easily in the various embodiments of the present invention.